feat: add compatibility with Postgres 17

[PaiJi]

No description provided.

[brody192]

We still deploy PG 16 by default, so I'm going to have to hold off on merging this for now as I do not know what adverse effects running pg_backup 17 on a PG 16 database could introduce, but thank you for the PR!

^ Though If you have any data on running pg_dump 17 with PG 16, I'd love to see it.

[pepijn-vanvlaanderen]

Dumping should be no problem with v17 for a v16 database. Only restoring a v17 dump into a v16 database could create issues.

Best would be to make the PG_VERSION adjustable maybe.

[brody192]

It is - https://github.com/railwayapp-templates/postgres-s3-backups/blob/main/Dockerfile#L23

If you set PG_VERSION yourself via a service variable, what you set will be used in place.

[pepijn-vanvlaanderen]

Ah I see, that is great. But v17 is not available on node 20, this PR is needed for that to work I guess.

Edit: I've opened a PR that is backwards compatible and allows users to configure the template for v17 as well: #32